Question

2.
If a = 9-4√5 than
find the value of a-1/a​

Answer 1

Answer:

9-4root5-1/9-4root5 take L.C.M. (9-4root5multiply by 9-4root5-1)/9-4root5, (81-36root5-36root5+16into25-1)/9-4root5, (80+72root5+400)/(9-4root5), 480+72root5/9-4root5 rationalise it. 480+72root5 multiply by 9-4root5/9-4root5 into 9-4root5. and further solve it.